code: def forward(
      cls, ctx, X, alpha=1.5, dim=-1, n_iter=50, ensure_sum_one=True
  ):
      p_m, backward_kwargs = _entmax_bisect_forward(
          X, alpha, dim, n_iter, ensure_sum_one, cls
      )
  
      ctx.alpha = backward_kwargs["alpha"]
      ctx.dim = backward_kwargs["dim"]
      ctx.save_for_backward(p_m)
      return p_m
  
imports: import torch
  import torch.nn
  from torch.autograd import Function
label_desc: Use image node_id 4 for calling the EntmaxBisectFunction obj's underlying member method code with example usage: obj.forward(cls, ctx, X, alpha, dim, n_iter, ensure_sum_one) and returns: p_m